The present invention relates to a substation system and more specifically to a substation system that applies information technology (IT) to apparatuses for protecting and controlling transformation equipment connected to the power system in order to reduce the size of the transformation equipment, enable autonomous automation, digitalize data, and effectively use the data by utilizing a network.
Among power systems, a power transmission system and a power distribution system are equipped with a substation that boosts or reduces outputs from a power generator or reduces voltage of the system. In addition to a transformer that boosts or reduces voltage, the substation has a device for collecting and distributing electric power, a device or system for controlling power flow, and a device for protecting and controlling devices located inside the substation.
For example, a circuit breaker used for a gas insulating switchgear (GIS) is equipped with a gas pressure sensor for detecting gas pressure, an acceleration sensor for detecting signals emitted in association with a problem, and a current and voltage detector; and a transformer is equipped with a thermometer, pressure gauge, oil-level sensor, and current detector as sensors that detect the state of the transformer.
These sensors are connected to a protection device, measuring device, control device, and device monitoring device via cables that transmit electric signals. Furthermore, the protection device, measuring device, control device, and device monitoring device are connected to a higher-rank substation monitoring and controlling device via individual cables that transmit electric signals.
The substation monitoring and controlling device monitors the state of the circuit breaker and the transformer based on the information obtained by various sensors, displays the monitored results on the screen, and outputs operation commands to the circuit breaker and the like. That is, it monitors the state of the substation at a remote location and remotely operates the circuit breaker and the like.
In conventional technology, a plurality of devices arranged at a lower-rank side are individually connected to the substation monitoring and controlling device via individual cables, thereby using several cables, which complicates the structure. Further, a plurality of lower-rank side devices are connected to each sensor, which uses several cables and even further complicates the structure. Furthermore, protection, control, and monitor of devices at a remote location also complicate the structure of the substation system. Moreover, the use of analog signals prevents effective use of data.
The objective of the present invention is to provide a substation system that enables simplification of the structure and effective use of data.
To solve said problems, the present invention comprises a state detector for detecting the state of monitored objects connected to a power system; a controller for controlling controlled objects connected to said power system according to control information; a monitor-information creating device for exchanging information with said state detector using digital signals as media and also creating information about the state of said monitored objects; and a control-information creating device for creating control information for controlling said controller, converting the created control information along with received control information into digital signals and transmitting the signals to said controller, wherein said monitor-information creating device and said control-information creating device are connected to a monitoring and controlling device for collecting information about the state of said monitored objects and outputting control information for controlling said controlled objects via a signal transmission path shared by those devices, and exchange information with said monitoring and controlling device using digital signals as media.